That looks like it would be part of package deals with entry level kits. I wonder if it's cheaper to make than the 9v Revvy, or just a style remake. When we see some dollar figures on it, then we'll know for sure. As far as using it for rental sets, why not? Anything to help the customer have a better experience their first time out is a plus. No more having to tell people to shake their guns and guess whether or not they're out of paint, two common complaints from the renter crowd. Yeah they'll have to replace batteries, but not until after several people use it if it's efficient on the battery. So, onwards in the name of customer satisfaction!